I'd like one of these for my identity.
Flip a single switch, and globally turn off identity sharing.
'Reduce, reuse, recycle' is actually a pretty good mantra for identity privacy.
Reduce corresponds nicely to minimal disclosure (i.e. reduce the amount of PII used in any transaction to only that necessary), reuse corresponds to controlled attribute sharing (i.e. reuse identity attributes stored in one network location at other locations/applications).
Not sure what it would mean to recycle identity ....